I. Field of the Invention
The present invention generally relates to three-dimensional all organic structures, and more particularly to three-dimensional organic interconnect structures for use in radio frequency and mixed signal module substrates and multilayer high-speed printed circuit boards.
II. Description of Related Art
Multilayer circuits typically comprise at least one conductive circuit layer bonded or laminated to a dielectric layer. The conductive circuit layer is generally a conductive metal such as copper, and the dielectric layer generally comprises a polymer resin such as epoxy. Depending on the selection of the dielectric layer and its thickness, the circuit can be either stiff or flexible.
Multilayer organic circuits incorporating thin film technologies are typically fabricated by parallel processing using diclad or monoclad layers that are sandwiched between bond ply materials to form a multilayer circuit construction. The number of metal layers can be as few as two and as many as sixty or more. The requirements for multilayer circuits in high density, high performance applications are becoming ever more demanding for high frequency applications. As a result there exists an unresolved need for a low cost multilayer process that can support both high frequency and high density (e.g., fine line and spaces, small via sizes) multilayer circuit constructions.